Anyobe here keep any kind of Knives? (Featherbacks)

[JMaffei]

I have heard conflicting information about the keeping of Royal Clown Knives, Clown Knives, and Gold/Albino Clown Knives. I have a 55ga set-up with 5 Parrots and 5 Knives (2 Royals, 2 Clown, and 1 Gold/Albino). I have been told that I cannot have more than one Knife (I prefer the featherbacks although I am also partial to the Black Ghost) in my tank due to aggression and territory issues. I have kept all of these fish together successfully for several months now without any incidents.

I would like to hear from any other members that have experience with knives (preferably featherbacks like I have). I would also like to know if anyone knows how to sex knives. I cannot get a straight answer for that question either!

If anyone is interested I can get some pics posted. I would really like to submit a pic of my Royals for the photo of the month as they are gorgeous, they are just a little camera shy though!

 

[Cichlidguy]

Woah, your talk is grosly overstocked. Did you know clown knives can grow up to 3'? You'll definately need to upgrade soon, because they can grow at an alarming rate. I would suggest the 180g (72 1/2 x 24 1/2 x 25 5/8) as a minimun for all those fish.

As for your questions.
1. Yes, as they grow older they will become more aggressive. Especially in close quarters.
2. Only god and the knives can tell the sexes apart. There also haven't been any reports of knives breeding in aquaria. Although I'm not sure its been accomplished.

 

[Hypostomus]

I agree. My knifefish grew too fast for me to even think about upgrading when it was kept on a varied, meaty diet. I did not keep it with other knifefish due to the environmental/aggression issues you mentioned, which generally surface when the fish grow larger. Mine was moved out of a 55g at 9" after about two years, but they can grow much faster than that (I read about one clown that got to 12" in one year, which I don't doubt is possible).

I remember reading somewhere that the BGKs were sexible, but as to clowns and royals I couldn't tell you.

Please return your knives, unless there is one in particular you want to keep, and plan on a *very* large tank to keep it in alongside some other large, peaceful fish. They are very gentle for such gigantic creatures, and you don't want to keep them with something boisterous that is going to bother them all the time.

Btw- my knife loved bloodworms, earthworms, shrimp pellets, dried krill, and feeder guppies that I cultured for it. Make sure it has a lot of variety.

 

[Christmasfish]

Black Ghost Knives are too mild tempered to keep company with the rough crew you have already. Clown Knives are actually aggressive predators once over the small fry stage and into the 6-7in + size. And they are quite territorrial in general. They grow super fast. And They are daring..our 7in (lip to fintip) rescue discus was savaged by 6 inch clowns as the shop patrons watched in horror.
The two royal fry I broght up from hitchhiking eggs grew uber fast and ate everything in the tank smaller than themselves. I sacrificed a whole spawn of gourami fry for them and a few betta and a few neon. For the credit I got.

You definitely have to part with some of those guys, change their company and plan in a larger tank. Lateral fish and bottom feeders require real estate measured in horizontal surface. Not just gallons.


All knives, but especially milder SA ones cannot be kept with fish that may damage their only form of locomotion. My poor guy has a heck of a time having only one pectoral that is a fin. Finipping aggressives can destroy them since they have only one major form of locomotion. And he started as a wee litttle fingerling and is now getting close to hitting the 10 inch mark...I got him for Valentine's.
And my BKG eats anything I offer him by hand...and snuffles around for scraps of favorites at the bottom. He is unerring at capturing fry and ghost shrimp. But has never attempted to eat the tetra..even when they were still small (the baby rummys were supposed to be his lunch!) And I have seen him yawn..he has a huuuge mouth like some plieasaur or somethin! Full of icy daggers. Lazy fish!
his favorites in order are scallop tidbits, micropellets and bloodworms.
hope that helps...that exhausts my on hand knife knowledge...... the rest is hearsay or things my lfs guys says. You might try the link to the Knifefish forum , it has a non-albifrons section. But it is mostly dedicated to ghosts.

Minifactoid: BKG are sexed by the shape of the mouth and the placement of the eyes.